Hi there,
I have the professional system with 10 amplified speakers.
The system itself is good.... very clear and decent bass. I do like extension in the low end so I am connecting an Infinity amplifier with an MTX subwoofer. It looks like it would be easy to replace the whole amplifier and the speakers as well, if you won't be satisfied with the custom speakers.
I haven't seen the logic system but as far as I understood it has fiber-optic cables which would make almost impossible to add an aftermarket amplifier.